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Aqueous Zn‐metal battery (AZMB) is a promising candidate for future large‐scale energy storage with commendable capacity, exceptional safety characteristics, and low cost. Acetonitrile (AN) has been widely used as an effective electrolyte constituent to improve AZMBs' performance. However, its functioning mechanisms remain unclear. In this study, we unveiled the critical roles of AN in AZMBs via comparative in situ electrochemical, gaseous, and morphological analyses. Despite its limited ability to solvate Zn ions, AN‐modulated Zn‐ion solvation sheath with increased anions and decreased water achieves a weakly‐solvating electrolyte. As a result, the Zn||Zn cell with AN addition exhibited 63 times longer cycle life than cell without AN and achieved a 4 Ah cm−2 accumulated capacity with no H2 generation. In V2O5||Zn cells, for the first time, AN suppressing CO2 generation, elevating CO2‐initiation voltage from 2→2.44 V (H2: 2.43→2.55 V) was discovered. AN‐impeded transit and Zn‐side deposition of dissolved vanadium ions, known as "crosstalk," ameliorated inhomogeneous Zn deposition and dendritic Zn growth. At last, we demonstrated an AN‐enabled high‐areal‐capacity AZMB (3.3 mAh cm−2) using high‐mass‐loading V2O5 cathode (26 mg cm−2). This study shed light on the strategy of constructing fast‐desolvation electrolytes and offered insights for future electrolyte accommodation for high‐voltage AZMB cathodes. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐metal battery (AZMB) is a promising candidate for future large‐scale energy storage with commendable capacity, exceptional safety characteristics, and low cost. Acetonitrile (AN) has been widely used as an effective electrolyte constituent to improve AZMBs' performance. However, its functioning mechanisms remain unclear. In this study, we unveiled the critical roles of AN in AZMBs via comparative in situ electrochemical, gaseous, and morphological analyses. Despite its limited ability to solvate Zn ions, AN‐modulated Zn‐ion solvation sheath with increased anions and decreased water achieves a weakly‐solvating electrolyte. As a result, the Zn||Zn cell with AN addition exhibited 63 times longer cycle life than cell without AN and achieved a 4 Ah cm−2 accumulated capacity with no H2 generation. In V2O5||Zn cells, for the first time, AN suppressing CO2 generation, elevating CO2‐initiation voltage from 2→2.44 V (H2: 2.43→2.55 V) was discovered. AN‐impeded transit and Zn‐side deposition of dissolved vanadium ions, known as "crosstalk," ameliorated inhomogeneous Zn deposition and dendritic Zn growth. At last, we demonstrated an AN‐enabled high‐areal‐capacity AZMB (3.3 mAh cm−2) using high‐mass‐loading V2O5 cathode (26 mg cm−2). This study shed light on the strategy of constructing fast‐desolvation electrolytes and offered insights for future electrolyte accommodation for high‐voltage AZMB cathodes. [ABSTRACT FROM AUTHOR]

Climate change and energy depletion are common worries of this century. During the global clean energy transition, aqueous zinc metal batteries (AZMBs) are expected to meet societal needs due to their large‐scale energy storage capability with earth‐abundant, non‐flammable, and economical chemistries. However, the poor reversibility of Zn poses a severe challenge to AZMB implementation. Coulombic efficiency (CE) is a quantitative index of electrode reversibility in rechargeable batteries but is not well understood in AZMBs. Thus, in this work, the state‐of‐art CE to present the status quo of AZMB development is summarized. A fictional 120 Wh kg−1 AZMB pouch cell is also proposed and evaluated revealing the improvement room and technical goal of AZMB chemistry. Despite some shared mechanisms between AZMBs and lithium metal batteries, misconceptions prevalent in AZMBs are clarified. Essentially, AZMB has its own niche in the market with unique merits and demerits. By incorporating academic and industrial insights, the development pathways of AZMB are suggested. [ABSTRACT FROM AUTHOR]

Due to the unsatisfactory electrode/electrolyte interface, the metallic Zn dendrites and corrosion are easily induced, severely hindering the applications of zinc-ion batteries (ZIBs). Herein, a strategy that engineers the interfacial double layer by an extremely low concentration of sulfolane is proposed to tune the Zn stripping/plating behavior. It is revealed that the highly-polar sulfolane can predominately occupy the inner Helmholtz layer over water, and then regulate the upcoming Zn2+ to directly deposit downward. Simultaneously, the widened Helmholtz layer can weaken the electric field intensity, which will generate more nucleation sites and reduce the nuclei radius, thereby promoting uniform zinc deposition as well. Moreover, corrosion byproducts can be inhibited since fewer water molecules can contact the Zn electrodes. Consequently, the battery performance can be naturally optimized. With an optimum amount of sulfolane, the Zn∥Zn battery can operate for more than 1,100 h under 1 mA cm−2 and 1 mAh cm−2. And the as-constructed Zn∥NaV3O8·1.5H2O battery demonstrates considerably higher cycling stability than that without sulfolane. Overall, this work has provided a deep insight into constructing a functional interfacial double layer to regulate zinc deposition, which can also act as a reference for other metal-based batteries. [ABSTRACT FROM AUTHOR]

This paper presents a 132–140 GHz power amplifier (PA) array in 0.13‐µm SiGe BiCMOS technology. The four dielectric‐loaded end‐fire antennas are integrated with the PA array on chip. With the absence of the lossy power combining networks at the output, the presented PA array achieves a measured maximal effective isotropic radiated power of 29.7 dBm. The array size is only 6.14 × 2.49 mm2 and consumes 5.16 W from a single 4 V DC supply. [ABSTRACT FROM AUTHOR]

Background: Macrophage receptor with collagenous structure (MARCO) reportedly plays a crucial role in the occurrence and development of several cancers. However, the association between MARCO and the prognosis of hepatocellular carcinoma (HCC) post-liver transplantation remains poorly elucidated. Methods: We examined MARCO expression at mRNA and protein level in 145 HCC samples and adjacent nontumor tissues using quantitative reverse transcription PCR, Western blot and immunohistochemistry. Furthermore, we analyzed the correlation of MARCO expression with clinicopathologic features and prognosis. Results: We assessed the association between MARCO expression and clinicopathologic features and used the Cox proportional hazards regression model to explore the association between MARCO expression and clinical prognosis of patients with HCC post-liver transplantation. We observed that the expression of MARCO at mRNA and protein level in adjacent nontumor tissues was higher than that in the HCC tissues. Low MARCO expression in HCC tissues was correlated with higher alpha-fetoprotein levels, higher incidence of microvascular invasion, and a higher number of patients beyond Milan criteria. Kaplan–Meier survival curves showed that patients with HCC with low MARCO expression exhibited poor overall survival (OS) and disease-free survival (DFS). Univariate and multivariate analysis revealed that MARCO expression was an independent prognostic factor for OS (hazard ratio [HR] 2.696, 95% confidence interval [CI] 1.335– 5.444, P=0.006) and DFS (HR 2.867, 95% CI 1.665– 4.936, P< 0.001) in patients with HCC post-liver transplantation. Based on immunofluorescence analysis, MARCO expression was primarily localized to macrophages and might be associated with M2-like macrophage polarization during HCC. Conclusion: MARCO expression was downregulated in HCC and associated with poor prognosis of patients with HCC post-liver transplantation. Moreover, it could be a potential prognostic marker and therapeutic target in post-liver transplantation HCC. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) have been intensively investigated as potential energy storage devices on account of their low cost, environmental benignity, and intrinsically safe merits. With the exploitation of high‐performance cathode materials, electrolyte systems, and in‐depth mechanism investigation, the electrochemical performances of ZIBs have been greatly enhanced. However, there are still some challenges that need to be overcome before its commercialization. Among them, the obstinate dendrites, corrosion, and hydrogen evolution reaction (HER) on Zn anodes are critical issues that severely limit the practical applications of ZIBs. To address these issues, various strategies have been proposed, and tremendous progress has been achieved in the past few years. In this article, we analyze the origins and effects of the dendrites, corrosion, and HER on Zn anodes in neutral and mildly acid aqueous solutions at first. And then, a scientific understanding of the fundamental design principles and strategies to suppress these problems are emphasized. Apart from these, this article also puts forward some requirements for the practical applications of Zn anodes as well as several cost‐effective‐modifying strategies. Finally, perspectives on the future development of Zn anodes in aqueous solutions are also briefly anticipated. This article provides pertinent insights into the challenges on anodes for the development of high‐performance ZIBs, which will greatly contribute to their practical applications. [ABSTRACT FROM AUTHOR]

This paper presents a D-band (110–170 GHz) transmitter/receiver (Tx/Rx) chipset with end-fire on-chip antennas (OCAs) using 0.13-μm SiGe BiCMOS technology. The input LO signal frequency of the chipset is 31.25 GHz. A 62.5-GHz frequency doubler, a D-band 2nd-harmonic up-conversion mixer, a power amplifier (PA), and an end-fire antenna are integrated in the Tx. An end-fire antenna, a D-band low-noise amplifier (LNA), a 2nd-harmonic down-conversion mixer, and a 62.5-GHz frequency doubler are integrated in the Rx. The end-fire OCA has gain and efficiency of 4.1 dBi and 83%, respectively. Maximum measured effective isotropic radiation power (EIRP) of 9.2 dBm and conversion gain of 21 dB are achieved for the Tx and Rx, respectively. The Tx/Rx are packaged on PCBs through wire bonding and chip-to-chip wireless communication using 16QAM modulation with the data rate of 4 Gb/s is demonstrated. The DC power consumption of the whole chip is ~1150 mW, and the total chip size is 2 × 3.5 mm2. [ABSTRACT FROM AUTHOR]

This paper presents the detailed design and demonstration of a Ka-band single-chip transmit (TX)/receive (RX) front-end in 0.13- \mu \textm SiGe BiCMOS technology. The front-end includes single-pole double-throw (SPDT) switches, low-noise amplifier, loss compensation amplifiers (LCAs), phase shifter, and power amplifier. Distributed structures are utilized in gain amplifiers to ensure broadband performance while stacked structure is adopted in power amplifier to deliver high output power in the TX mode. A 5-b phase shifter with design strategies for low rms phase/gain errors serves as the common leg of the RX and TX paths. In the RX mode, measurements show a gain of 17 dB, an output P\mathrm { {-1~dB}} of −1 dBm, an rms phase error less than 4°, and an rms gain error less than 0.6 dB with 0.528-W dc power from 30 to 40 GHz. In the TX mode, measurements show a gain of 14 dB, an output P\mathrm { {-1~dB}} of 20.5 dBm, an rms phase error less than 3.7°, and an rms gain error less than 0.55 dB with 1.587-W dc power from 30 to 40 GHz. The whole front-end occupies $3.2 \times 2.2$ mm2 including the testing pads. By choosing inductors and capacitors with reasonable values, designing a well-matched SPDT switch with high isolation, and optimum ordering of phase shift cells and LCAs in the phase shifter design, this TX/RX front-end achieves excellent rms phase/gain error performance without any trimming in a system-level measurement at Ka-band. [ABSTRACT FROM AUTHOR]

This paper presents the design of an X-band phased-array transceiver core chip in 0.13-\mu\m SiGe BiCMOS technology. The system is based on the all-RF architecture and contains switches, low-noise amplifier (LNA), power amplifier (PA), and the common leg 5-bit phase shifter with loss compensation amplifiers. A distributed structure is used in the gain amplifiers design to ease the multi-stage gain roll-off in the transmit (TX)/receive (RX) paths. A distributed LNA is utilized in the RX path to achieve broadband amplification with acceptable noise figure (NF) while a stacked PA is utilized in the TX path to get high output power. In the RX mode, the receiver demonstrates a gain of > \25 dB, an average NF of 3 dB, an output P -1~dB of 6 dBm, a root mean square (rms) phase error less than 3.8^\circ and an rms gain error less than 1.2 dB from 9 to 11 GHz; while dissipating 352-mW dc power. In the TX mode, the transmitter demonstrates a gain of > \22 dB, an output P -1~dB of 28 dBm, an rms phase error less than 3^\circ, and an rms gain error less than 0.6 dB from 9 to 11 GHz; while dissipating 4.128-W dc power. The whole transceiver occupies 5.2\,\times\,3 \mm^2 chip area including the testing pads. [ABSTRACT FROM PUBLISHER]

A 340-GHz on-chip antenna (OCA) with high-gain and high-radiation efficiency is designed using a standard 0.13\-\upmu m SiGe BiCMOS technology without any postprocesses. In the proposed OCA structure, a rectangular slot loop is etched in the upper wall of a substrate integrated waveguide (SIW) to form a magnetic current loop radiator. The SIW structure forms a back cavity to suppress the surface waves and separate the radiation aperture from the low-resistivity substrate. Furthermore, the side wall of the SIW cavity and the edge of the slot form a ${{{\lambda }}_{{g}}}/4$ resonator to reflect the power back to the slot loop. As a result, the radiation efficiency is improved. By etching a slot properly in the SIW upper wall, another resonating point is constructed and hence, the bandwidth is broadened. Single antenna element and a {2} \times {2} array are both designed and fabricated with- and without- the slot structure; a maximum gain of 7.9 dBi with the radiation efficiency of 48% at 340 GHz is achieved for the proposed SIW cavity-backed antenna structure. [ABSTRACT FROM PUBLISHER]

A 7.7-12 GHz fully monolithic transformer-coupled cascode power amplifier (PA) was designed for X-band phase array radar application. This PA was fabricated in a 0.25- $$\upmu $$ m SiGe BiCMOS technology with chip size of $$2\times 2$$ mm $$^{2}$$ . The best choice of the cascode topology for PA design is discussed and the possible stability issue of this configuration is analyzed. The distributed capacitor structure which is connected to the base of cascode transistor is proposed to reduce the base series inductance and hence, improve circuit stability and boost gain. Moreover, circuit/layout co-design for above structure is completed through full 3D simulation. The PA features a three-stage cascode architecture that includes both medium-speed (medium breakdown voltage) and high breakdown voltage (low-speed) SiGe transistors, and a 1:2 input splitter and a 4:1 output combiner which are designed for a low insertion loss and compact dimensions on-chip. The proposed PA achieves a measured small signal gain of 26.6-29.6 dB from 7.7 to 12 GHz with a 5.0 V DC supply. A 28 dBm maximum output power with an 18.5 % power-added efficiency at 10 GHz have also been achieved. [ABSTRACT FROM AUTHOR]

ABSTRACT This letter presents a 340 GHz fundamental on-off keying modulator using 0.13 μm CMOS technology. The proposed modulator topology is composed of a 90° hybrid coupler and two series loads formed by a series inductor and a MOSFET for 340 GHz on-/off-state switching. The measured results indicate that the insertion loss is ∼4.9 dB on average and the isolation is better than 13 dB from 330 to 347 GHz. A measured data rate of 2.5 Gb/s is demonstrated at the carrier frequency of 340 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1166-1168, 2015 [ABSTRACT FROM AUTHOR]

A sub-terahertz frequency doubler with signal modulation is proposed and analyzed in this letter. An 85 GHz input signal is modulated by a differential pair, and a push-push frequency doubler with capacitive degeneration technique is designed to obtain the 170 GHz modulated output signal. Via the use of negative impedance to eliminate the leakage current of transistors, the proposed enhanced push-push frequency doubler achieves a power efficiency of 8.5% and a maximum output power of 4.5 dBm at 170 GHz without applying a modulation signal. The 0.13 \mum SiGe BiCMOS process is used to fabricate the proposed design and the total chip area is 0.75\,\times\,0.8 mm^2. [ABSTRACT FROM PUBLISHER]

A cascade distributed amplifier (DA) is designed and analyzed in this letter. The proposed DA is fabricated in 0.13 \mum SiGe HBTs process and patterned ground micro-strips are deployed for the design of distributed inductors to achieve high-Q in the transmission line (TL). In addition, negative resistors and capacitors are used to widen the bandwidth. Gain boosting techniques are also used to ensure gain flatness throughout the band. The fabricated DA achieves an average gain of 17.5 dB and 14.5 dB gain at 110 GHz. 7.5 and 2.7 dBm saturated output power are obtained at 50 and 100 GHz, respectively. The total chip size is 0.8 mm \times 1.8 mm, including the bond pads. [ABSTRACT FROM PUBLISHER]

The traps in an AlGaN/GaN metal‐insulator‐silicon‐high‐electron‐mobility‐transistor on silicon are investigated by analysing the random‐telegraph‐signal (RTS) noise in the drain current. Two different types of RTS noise due to the traps at the gate‐oxide and AlGaN have been observed in this reported work. Through the analysis of the two RTS noises, the presences of the two trap types are verified and the trap locations have also been identified. [ABSTRACT FROM AUTHOR]